Mechanically Decoupled vs. Independent Ceiling

Hi Everyone! I'm new to this particular forum, but have been around for a while. I have a quick question on ceiling isolation for any construction experts around here. I'm currently in the process of designing a small rehersal space located in an attic. The attic floor and walls are 30cm reinforced concrete, and there is no structural ceiling present (aside from thermal insulation in aluminum framing and roofing tiles on top). The inner room itself is designed as a simple floating room: Insulated wood framing + hardwood floor, walls are built on the floating floor and mechanically decoupled from the structural walls. Under "regular" circumstances (where a structural ceiling exists) I would probably design an independent ceiling hanging from the structural one. But since I'm floating the whole space, I was wondering which of the following options would be more adequate (isolation-wise) in your opinion: A) Have the construction engineer design a typical structural ceiling, and then design an independent ceiling supported by the structural ceiling hanging on whatever isolation channels. B) Regardless of the structural ceiling, design an inner ceiling supported by the inner room framing and decoupled from the structural ceiling. The way I see the pros/cons is: for option (A): I can load the isolation system with much more mass, since it is supported by the structural ceiling. for option (B): I can't load the inner ceiling a lot, but I gain complete mechanical decoupling from the structural ceiling. Any opinions on this?

Hi Jonessy , how is the wheater in Israel ? Here today it's -1Celcius under 15cm of partly melted snow...yuk i ain't no "expert" but i'll give it a shot ! Isolation wise from my point of view definitely go with solution B, an independent ceiling mounted on top of your inner room walls. Saying that you can't load this ceiling as much as the structural one is an half truth IMHO. If properly design this won't be a problem. what is the available ceiling height ? Suspended ceiling are much more tricky to build IMHO and not as good (isolation wise) if they happen to touch any inner walls surface you just work for nothing. That won"t be a problem if you do it the other way. First make sure that the floor on wich you plan to build you studio can take the load. A Concrete floor doesn't mean it can take an infinite amount of additional dead load. Have this check first. Find a way to add mass to your outer leaf ceiling (the roof) if you can. In your situation i am not sure you need to float your floor. Although it may sound counterintuitive it can in fact make things worst (inside the room). Have a drummer play, or any low frequency source in the space and then go on the floor underneath my guess is that you can't hear it through the concrete floor It takes a lot of energy to move 30cm of concrete ! :wink: Some impact sound may get through but airborn sound...not sure Hope this help

Hi orangenumerik, Whether here is not too bad. Beginning of winter. :) I'm going to consult with the construction engineer of this project and see how much load I can put on the floor. I recalculated a few parameters in the design, and I might need to rethink the whole decoupling approach. Thanks anyway, Cheers, Jon.